People use lemons to make lemonade by mixing lemon juice and water. Many people also use lemon as a washing agent, because of its ability to remove stains. The scent of lemon can also repel mosquitoes, while drinking lemon juice with olive oil helps to get rid of gall stones. Lemon is well known for its medicinal power and is used in many different ways. As per the results reported in a study by the Annals of the Rheumatic Diseases, lemon provides protection against inflammatory polyarthritis and arthritis.